104 These are a few of our videos for analysis in the conceptual classes. The last clip in the video is in “instant replay” mode. Students will be producing several graphs and answering questions designed to help them connect projectile motion to the balanced force model and the unbalanced force model.




Free Fall

102 When we investigate free fall, we drop picket fences, and we also fling them upward using rubber bands. This does not work every time, but it is quick enough to get five good trials with usable slopes. We compare the slopes of these graphs to the slopes of graphs made with the dropped picket fences.




96 The data are starting to come in from the video analysis. Not enough yet to tell what the graph will look like. I decided to pull all the data together in a Google Doc.



20130128-153003.jpg89 (Yeah, missed a few days. Last week was “Quarterly Assessment” week and was not very photogenic.) Today the conceptual classes are applying Newton’s 2nd Law to the motion of elevators. Since I don’t want any student to feel obligated to reveal their weight to their classmates, I am the one who gets to stand on the bathroom scale. We use the differences in the scale reading when starting to move and when coming to a stop (compared to standing still) to determine the acceleration of the elevator at different points in its motion. I’m wearing my favorite brown boots in this photo, and they are pretty heavy. 😉


Inversely Proportional

20130116-145601.jpg82 We are nearly finished analyzing the data from the Newton’s 2nd Law lab. This is the first time this year that the conceptual students have had to deal with an inverse proportion, so that is new. The shapes of the graphs look nice, but we haven’t checked to see how the slope values match up with what they should be. We are not quite there yet.

This post is actually for today. Today is the 82nd day of school. 😉



N2 Lab


75 It is time for the conceptual classes to learn about the relationship between acceleration, force, and mass. We’re doing modified Atwood’s, varying total system mass first. As you can see, we are not a single-vendor school. I don’t even know where those little hanging mass sets come from, but I like them!